Techjav: New in Firefox 28, Youtube 4K video, Web notification

Firefox released version 28
Here are the list of changes with all the details:

VP9 video decoding introduced
VP8 is already used in WebM video formats, commonly in YouTube's html5 video players.
VP9 videos are smaller than VP8 video (because of upto 50% less bitrate) while having the same quality.
VP9 will be used in YouTube's 4K video streaming, so who ever has got that God like internet speeds can check it out.

You can test if your web browser supports VP9 here
http://base-n.de/webm/VP9%20Sample.html

Mac users now have Notification center support for web notifications

Pic from http://9to5mac.com/

Horizontal HTML5 volume control

Firefox 27

Firefox 28

Opus audio codec support for WebM
With VP9 on video, Opus has been introduced for audio. It allows lower bitrate (therefore smaller file size) and lower latency audio.
You can hear the benefits of opus here:
https://auphonic.com/blog/2012/09/26/opus-revolutionary-open-audio-codec-podcasts-and-internet-audio/

SPDY protocol support for version 2 was dropped in favour of version 3

Developer related changes:

MathML has partial support for mathvariant attribute

MathML allows Web browsers to render Math experssions. MathML is only supported by Firefox.

mathvariant will allow typography such as bold, italic, bold-italic, monospace, sans-serif etc. on the expressions.

Multiline Flexbox support
Flexbox allows a Web developer to clearly organise a webpage layout without any hacks.
Though Firefox supported flexbox from older versions, having more than one rows was an issue.
Firefox 28 will fix that.